<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .head .a{
            color: red;;
        }
    </style>
</head>
<body>
<div class="head">
    <ul>
        <li>
            <div class="a">aaa</div>
            <div>bbb</div>
        </li>
    </ul>

    <div>ccc</div>
    <p class="a">ppppp11111111</p>
    <p>ppppp333333</p>
</div>
<div class="head">

    <div>xxxx</div>
    <div>yyyy</div>
    <div class="a">zzzz</div>

    <p>ppppp</p>
    <p>ppppp</p>
</div>
<div class="a">z1111111111111111
    <div  class="head">z22222222222
        <div class="a">z3333333333333333</div>
    </div>
</div>
</body>
</html>